Alleged Long Island Gilgo Beach Serial Killer Had a Blueprint to ‘Plan Out His Kills,’ Prosecutors Say

Prosecutors claim the suspect in the "Gilgo Beach killings" allegedly documented his killings in detail on his computer. Rex Heuermann, the accused serial killer from Long Beach, New York, used a “planning document” to “methodically blueprint” the murders, CNN reported, citing police.

Prosecutors alleged the document detailed how he was to select, kill, and dispose of his victims. They also claimed Heuermann had deleted the document from his hard drive, but police utilized forensic means to retrieve this piece of evidence.

The word document had allegedly been created in 2000, and over the years had been updated, as Heuermann allegedly killed more people, prosecutors said, according to CNN.

Prosecutors are hopeful that the document will help them to establish intent with regards to the murders, ABC News reported. "I think it, first and foremost, evinces a certain intent, and that intent is to hunt and capture and kill females," Suffolk County District Attorney Raymond Tierney told the outlet.

The document was found on March 7, 2024, in a laptop's unallocated space, according to prosecutors, who noted the alleged evidence strengthens their case against Heuermann. Officials noted the retrieval of the document was not easy for detectives as they had to make their way through a wealth of tech items recovered from Heuermann, an architect by profession.

Detectives reportedly combed through 27 computers, 58 internal hard drives, along with another 22 external drives, as well as 15 types of cameras. The suspect also had a hoard of memory cards, USB devices, and SIM cards.

The document was discovered almost a year after charges were filed against Heuermann, in July 2023. The Long Island architect has entered a not-guilty plea for all of those charges.

On June 6, Heuermann was also charged in connection with the 2003 murder of Jessica Taylor, whose remains were found on Long Island at Gilgo Beach and in Manorville, and the 1993 murder of Sandra Costilla, whose remains were found in North Sea, Long Island, in 1993, ABC News reported.

The prosecution has now compounded the charges and added four more women to the list. These women were killed across three decades and belonged to various communities.

Heuermann was previously charged with murders of Melissa Barthelemy, Megan Waterman, Amber Costello and Maureen Brainard-Barnes. These four are collectively called the “Gilgo Four.” They were found bound with belts or tape and wrapped in burlap along a stretch of Gilgo Beach all through 2010, CNN reported.

The Word document was organized with headings that included “Supplies” and “Problems.” DNA was the first item listed in the latter category.

The DNA evidence collected against Heuermann and this document could form the crux of the prosecution's argument against him, Casey Jordan, a criminologist, behavioral analyst, and attorney shared with CNN. 

“The fact that he tried to get rid of these documents and that they were still found on the computer memory is really going to be – in connection with the DNA – a kind of nail in the coffin,” Jordan said. “These two things combined are going to be very difficult for the defense to overcome,” added Jordan.

Heuermann was identified as a person of interest in 2022 based on cell phone data, witness description, and other information, CNN reported. Investigators gained a huge breakthrough in the case when they were able to locate Heuermann's DNA near several dead bodies in January 2023.

The team took a swab from leftover pizza crust Heuermann allegedly discarded in the trash outside his Manhattan office, according to court documents. They matched the DNA found from the pizza to the hair they found on the burlap sack where the remains of one of the victims, Megan Waterman, were found.

The latest bail application states that two forensic laboratories determined hairs recovered on five of the six victims were tied to Heuermann and people who lived around him, CNN reported.

Heuermann's attorney Michael Brown told reporters that he and his team need more time to review the evidence before making any comment.

Brown accepted that the compounding of charges makes things difficult for his client. “One murder is obviously horrific, and it’s a difficult thing to defend,” said Brown, CNN reported. “And now we’re at six.”